#include <iostream>
#include <unistd.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <string.h>
#include <cstring>

// ./tcpclient server -ip server -port
int main(int argc,char*argv[])
{
      if(argc!=3)
    {
        std::cerr<<"Usage :"<<argv[0]/*可执行程序对应的名称*/<<"server ip,server port"<<std::endl;
        exit(0);
    }
    std::string serverip=argv[1];
    uint16_t serverport =std::stoi(argv[2]);
    int sockfd =::socket(AF_INET,SOCK_STREAM,0);
    if(sockfd <0)
    {
        std::cerr <<"create socket error"<<std::endl;
        exit(1);
    }

    //不需要显示的bind，但是一定要有自己的IP和port，所以需要隐式的bind,os自动绑定
    //客户端不需要监听，也不需要accept
    struct sockaddr_in server;
    memset(&server,0,sizeof(server));
    server.sin_family=AF_INET;
    server.sin_port=htons(serverport);
    // server.sin_addr.s_addr=
    ::inet_pton(AF_INET,serverip.c_str(),&server.sin_addr);


    int n=::connect(sockfd,(struct sockaddr *)&server,sizeof(server));
    if(n<0)
    {
        std::cerr <<"connect socket error" <<std::endl;
        exit(2);
    }
    while(true)
    {
        std::string message;
        std::cout<<"Enter #";
        std::getline(std::cin,message);

        write(sockfd,message.c_str(),message.size());

        char echo_buffer[1024];
        n=read(sockfd,echo_buffer,sizeof(echo_buffer));
        if(n >0)
        {
            echo_buffer[n] =0;
            std::cout<<echo_buffer<<std::endl;//输出
        }
        else
        {
            break;
        }
    }
    ::close(sockfd);
    return 0;
}